dbix::class::filtercolumn(3pm) [debian man page]

DBIx::Class::FilterColumn(3pm)				User Contributed Perl Documentation			    DBIx::Class::FilterColumn(3pm)

NAME

       DBIx::Class::FilterColumn - Automatically convert column data

SYNOPSIS

       In your Schema or DB class add "FilterColumn" to the top of the component list.

	 __PACKAGE__->load_components(qw( FilterColumn ... ));

       Set up filters for the columns you want to convert.

	__PACKAGE__->filter_column( money => {
	    filter_to_storage => 'to_pennies',
	    filter_from_storage => 'from_pennies',
	});

	sub to_pennies	 { $_[1] * 100 }

	sub from_pennies { $_[1] / 100 }

	1;

DESCRIPTION

       This component is meant to be a more powerful, but less DWIM-y, DBIx::Class::InflateColumn.  One of the major issues with said component is
       that it only works with references.  Generally speaking anything that can be done with DBIx::Class::InflateColumn can be done with this
       component.

METHODS

   filter_column
	__PACKAGE__->filter_column( colname => {
	    filter_from_storage => 'method'|&coderef,
	    filter_to_storage	=> 'method'|&coderef,
	})

       This is the method that you need to call to set up a filtered column. It takes exactly two arguments; the first being the column name the
       second being a hash reference with "filter_from_storage" and "filter_to_storage" set to either a method name or a code reference. In either
       case the filter is invoked as:

	 $row_obj->$filter_specification ($value_to_filter)

       with $filter_specification being chosen depending on whether the $value_to_filter is being retrieved from or written to permanent storage.

       If a specific directional filter is not specified, the original value will be passed to/from storage unfiltered.

   get_filtered_column
	$obj->get_filtered_column('colname')

       Returns the filtered value of the column

   set_filtered_column
	$obj->set_filtered_column(colname => 'new_value')

       Sets the filtered value of the column

EXAMPLE OF USE

       Some databases have restrictions on values that can be passed to boolean columns, and problems can be caused by passing value that perl
       considers to be false (such as "undef").

       One solution to this is to ensure that the boolean values are set to something that the database can handle - such as numeric zero and one,
       using code like this:-

	   __PACKAGE__->filter_column(
	       my_boolean_column => {
		   filter_to_storage   => sub { $_[1] ? 1 : 0 },
	       }
	   );

       In this case the "filter_from_storage" is not required, as just passing the database value through to perl does the right thing.

perl v5.14.2							    2010-12-25					    DBIx::Class::FilterColumn(3pm)

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DBIx::Class::Helper::Row::StorageValues(3pm)		User Contributed Perl Documentation	      DBIx::Class::Helper::Row::StorageValues(3pm)

NAME

       DBIx::Class::Helper::Row::StorageValues - Keep track of stored vs in-memory row values

VERSION

       version 2.013002

SYNOPSIS

	package MyApp::Schema::Result::BlogPost;

	use parent 'DBIx::Class::Core';

	__PACKAGE__->load_components(qw(Helper::Row::StorageValues));

	__PACKAGE__->table('BlogPost');
	__PACKAGE__->add_columns(
	   id => {
	      data_type 	=> 'integer',
	      is_auto_increment => 1,
	   },
	   title => {
	      data_type 	 => 'varchar',
	      length		 => 32,
	      keep_storage_value => 1,
	   },
	   body => {
	      data_type => 'text',
	   },
	);

	1;

	# elsewhere:

	my $post = $blog_rs->create({
	  title => 'Components for fun and profit',
	  body	=> '...',
	});

	$post->title('Components for fun');

	warn sprintf 'Changing title from %s to %s',
	  $post->storage_value('title'), $post->title;

	$post->update;

DESCRIPTION

       This component keeps track of the value for a given column in the database.  If you change the column's value and do not call "update", the
       "storage_value" will be different; once "update" is called the "storage_value" will be set to the value of the accessor.  Note that the
       fact that it uses the accessor is an important distinction.  If you are using DBIx::Class::FilterColumn or DBIx::Class::InflateColumn it
       will get the non-storage or inflated values, respectively.

METHODS

   _has_storage_value
	$self->_has_storage_value('colname')

       returns true if we should store the storage value from the database.  Override this if you'd like to enable storage on all integers or
       something like that:

	sub _has_storage_value {
	   my ( $self, $column ) = @_;

	   my $info = $self->column_info($column);

	   return defined $info->{data_type} && $info->{data_type} eq 'integer';
	}

   storage_value_columns
	$self->storage_value_columns

       returns a list of columns to store

   get_storage_value
	$self->get_storage_value('colname')

       returns the value for that column which is in storage

AUTHOR

       Arthur Axel "fREW" Schmidt <frioux+cpan@gmail.com>

COPYRIGHT AND LICENSE

       This software is copyright (c) 2012 by Arthur Axel "fREW" Schmidt.

       This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

perl v5.14.2							    2012-06-18			      DBIx::Class::Helper::Row::StorageValues(3pm)

Linux and UNIX Man Pages

dbix::class::filtercolumn(3pm) [debian man page]

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